The transition-metal–boron bonding interactions and geometric structures of heterodinuclear transition metal carbonyl cluster cations BM(CO)_n⁺ (M = Co, Ni, and Cu) are studied by a combination of the infrared photodissociation spectroscopy and density functional theory calculations at the B3LYP/def2-TZVP level. The BCu(CO)₅⁺ and BCo(CO)₆⁺ cations are characterized as an (CO)₂B–M(CO)_3/4⁺ structure involving an σ-type (OC)₂B → M(CO)_3,4⁺ dative bonding with end-on carbonyls, while for BNi(CO)_5,6⁺ complexes with a bridged carbonyl, a 3c–2e bond involving the 5σ electrons of the bridged carbonyl and an electron-sharing bond between the B(CO)₂ fragment and the Ni(CO)_2,3⁺ subunits were revealed. Moreover, the fundamental driving force of the exclusive existence of a bridged carbonyl group in the boron–nickel complexes has been demonstrated to stem from the desire of the B and Ni centers for the favorable 8- and 18-electron structures.

中文翻译：

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质量选择双核过渡金属硼化物羰基簇阳离子的红外光解光谱

通过红外光解离光谱和密度泛函理论计算的结合，研究了异双核过渡金属羰基簇阳离子 BM(CO) _n ⁺ (M = Co、Ni 和 Cu) 的过渡金属-硼键相互作用和几何结构。 B3LYP/def2-TZVP 水平。 BCu(CO) ₅ ⁺和 BCo(CO) ₆ ⁺阳离子的特征为 (CO) ₂ B–M(CO) _3/4 ⁺结构，涉及 σ 型 (OC) ₂ B → M(CO) _{3 ,4} ⁺与末端羰基形成配位键，而对于具有桥接羰基的 BNi(CO) _5,6 ⁺配合物，涉及桥接羰基的 5σ 电子的 3c–2e 键和 B( CO) ₂片段和 Ni(CO) _2,3 ⁺亚基被揭示。此外，硼镍配合物中桥连羰基的唯一存在的基本驱动力已被证明源于B和Ni中心对有利的8和18电子结构的需求。